Silencer for internal-combustion engines



Dec. 28 1926.

W. HUNTER ET AL SILENCER FOR INTERNAL COMBUSTION ENGINES Filed, Jan. 5. 1923 Patented Dec. 2a, 1926. L

' UNITED-STATES WILLIAM HUNTER AND MAY GILL, OI BLACKPQOL, ENGLAND.

SILENCEB FOB INTERNAL-COMBUSTION ENGINES.

' Application filed January 5, 1923, Serial No. 810,845, and in Great Britain September 80, 1822.

Thisinvention 'relates to improvements in silencers for internal combustion engines. The object of the resent invention is to provide a silencer which is eflicient in operation and provides no back pressure to the exhaust of the en inc and at the same time is simple to manu acture. In the drawings which show one embodiment of the present invention 'Fi 1 is a view in longitudinal section of the evice, and

2 is a section on the line 2-2 of e invention is directed broadly to a silencer of the ejector type provided with baflle means.

Referring in detail to the drawings the device com rises essentially a cylindrical casing I to w ich are attached by threads 2 or other suitable means, conical. end pieces 3 and 4. The end piece 3 is provided with suitable clamping means 5 for attaching the silencer to the exhaust pipe ofthe eng Mounted within the cylindrical casing 1 is an eject-or .tube 6 centralilg disposed ca 'ing a continuous iral be e 7. Between t e inlet end of the e ector tube 6 and the com mencement of the spiral baflle is a space 8 forming a stabilizing chamber. Mounted on the inlet end of the ejector tube is a perfor ated baflle plate 9 the perforations being shown at 10. The diameter of said plate "is slightly in excess of the-inner diameter of $5 the casing land the plate is held between the inlet end of the casing 1 and a flange 11 formed on the inner face of the end piece 3. In this way the ejector is conveniently mounted within the casing -1.

The ejector tube 6 has at its exhaust end a nozzle 12 which is adapted to project w1thin the cone portion of the end piece 4.

The spiral baflle 7 .is mounted on the upper surface of'the ejector tube 6 and the d15- tance between each succeeding convolution is such that the area for the passa e of the gases bounded by the spiral baflie and the outer casing 1 is directly or suitably proportioned to the area of the opening of the exhaust valve in view of the time factor involved. The area of entrance to the spiral is never less than the area of the exhaust The area of the perforations 10 1n the bafile plate 9 is greater than the area of the time to allow of an uninterrupted afil thence through the spiral passage exterior exhaust pipe. The spiral baflle 7 is extended slightly in a direction substantially parallel to the axis of the ejector tube 6 for a short distance at the beginning and end of said baflie. v 1

The continuous spiral bafile 7 is preferabl formed of a plurality of annular discs whic are split along one radius and the ends drawn out in opposite directions substantially parallel with the axis of the disc. In

this way each disc forms one complete convolution. The separate convolutions are riveted or otherwise secured as shown at 13 to form a continuous spiral bame which is mounted on the ejector tube in any suitable manner such as by brazing at certain points indicated by 14.

It will be understood that the size of the aperture of the ejector tube and the size of the passage formed by. the bafile may be varied to suit the particular type of engine with which the silencer is to be used.

The stabilizing chamber 8 used in combination with a-continuous spiral baflle has been found of considerable importance in obtaining an eflicient practical result. The function of the stabilizing chamber is to stabilize the exhaust gases which are admitted to the silencer with considerable velocity and to avoid any turbulence which would otherwise be set up and at the same passage of the gas between the spiral es. The method of operation of this device is essentially simi at to other ejector devices of a similar nature in that the action of the ejector tub'e causes the gas to be drawn simultaneously mto the stabilizing chamber and of the said e ector tube.

We claim as our invention A silencer for internal combustion engines comprising in combination, a cylindrical casing, a conical end' piece mounted on the rear end of said casing, a conicalend piece mounted on the front end of said casin and provided with a shoulder on its inner ace, a tube concentric with said cylinder and adapted to form an uninterrupted passage for exhaust gases, an ejector forming a part of said tube, a baflie late formed integrally with said tube an secured between the front end of said casing and the shoulder of said conical end piece, a continuous uninterrupted spiral bafile plate extending between the outer surface of said tube and tach said forward conical member to the the inner surface of said casing andmountexhaust pipe of the amine.

ed on said ejector tube to'leavc a substan- In witness' Whereo-we have hereunto 10 tial chamber between. said baflie plate and signed our names this 20 day of December, the commencement ofthe spiral bafiie in or 1922. r

5 der to form a stabilizing chamber for the WILLIAM HUNTER.

prevention ofturbulence and means to at- MAY GILL 

